Research on TL1A has focused on autoimmune diseases where immune complexes are formed, e.g. rheumatoid arthritis. However, studies have suggested that early pathogenesis in psoriasis could dependent on formation of large complexes between bacterial DNA and the anti-microbial peptide LL-37 which induce cytokine secretion from APC. Cytokines that could lead to TL1A excretion. Whether TL1A can be secreted in this way is unknown.